Re: Peformance problem with mv

From:

Jim Meyering

Subject:

Re: Peformance problem with mv

Date:

14 Mar 2001 16:42:18 +0100

User-agent:

Gnus/5.09 (Gnus v5.9.0) Emacs/21.0.100

Thanks for the report.
4.0p is more than a year old, but even so, I'd be surprised
to learn that it is copying files instead of using renaming.
If you can show that mv from the latest test release
ftp://alpha.gnu.org/gnu/fetish/fileutils-4.0.41.tar.gz
is copying (rather than using rename) files on the same device,
then please let me know. To verify what it's doing, you can run
strace -o log uml/* fs
then look in the `log' file to see if it used rename (as expected)
or read/write (to copy).
If your disk was really full, you may well have run out of space
because the destination directory had to grow but couldn't.
John Summerfield <address@hidden> wrote:
| I have GNU fileutils 4.0p installed on Red Hat Linux 6.2.
|
| I have some files about 420 Mbytes in size, and I tried to move them from one
| directory to another on the same device.
|
| The command I used was
| mv uml/* fs/
|
| What I expected to happen is logically equivalent to
| ln uml/FILE fs/FILE
| rm uml/FILE
|
| for each file.
|
| What mv actually attempted was to copy the files with the result it took ages
| and then ran out of space.
|
| I eventually got round the problem by shuffling directory names and that
| worked well.
|
| I'm baffled as to why it attempted what it did, but there is no room for
| doubt: I ran out of disk space.